1. Field
Although not so limited in its utility or scope, implementations of the present invention are particularly well suited for incorporation in material sortation systems such as those used in moving mail pieces through various stages of processing in a mail processing facility, for example.
2. Brief Description of an Illustrative Environment and Related Art
Material handling operations frequently involve the use of transport systems including networks of conveyor belts, roller conveyors, conduits and chutes. In a typical material sorting environment, a material receptacle is located at each terminus of a selected plurality of termini for the collection of material exiting the sortation system. Commonly, a discharge chute corresponds to a terminus and includes a surface sloped downwardly toward the receptacle for guiding material exiting the sortation system into the receptacle situated below the chute. Illustrative, commonly used, material receptacles include flexible receptacles such as sacks and bags, for example, and rigid receptacles such as boxes, crates, cartons, and carts, for instance.
In a typical package or mail sortation system, multiple, adjacent discharge chutes are arranged along a base structure such as a longitudinally extending main framework adapted for supporting plural chutes. Each chute, and the receptacle corresponding thereto, is typically dedicated to guiding and retaining mail pieces destined for a particular geographical region. Depending on the level of sortation refinement to which a set of chutes and receptacles is dedicated, each chute within the set may be dedicated to mail pieces destined for a particular region of the country, a particular state, a region of a state identifiable by the first three or four digits of a ZIP Code or destination city, for example. A reality of mail sortation systems is that a small percentage of mail pieces exits the sortation apparatus prematurely (i.e., without settling in appropriate receptacles). Of the mail pieces that are unintentionally expelled from the sortation apparatus, a considerable percentage travel as far as the discharge chute and simply miss the receptacle and come to rest on the work area floor, thereby contributing to the xe2x80x9cmiss sort errorxe2x80x9d rate of the overall sortation system. For various reasons, sortation protocol in certain sorting facilities requires the reintroduction into the system of unintentionally expelled mail pieces. Consequently, unintentionally expelled mail pieces handled in accordance with the aforementioned protocol must be xe2x80x9cdouble handledxe2x80x9d by at least a portion of the mail sorting apparatus. As will be readily appreciated, since a given set of mail sortation apparatus can handle only a finite number of mail pieces per unit time, the xe2x80x9cdouble handlingxe2x80x9d of mail pieces by any portion of the mail sorting apparatus decreases the efficiency of the overall sortation system.
In response to miss-sort errors in the vicinity of receptacles, sortation facility personnel have resorted to various improvised measures. For instance, it is not uncommon for sortation personnel to raise the front of a receptacle (i.e., the opening edge of the receptacle opposite the exit end of the discharge chute) with the intention of creating a xe2x80x9cback stopxe2x80x9d for mail pieces that might otherwise overshoot the receptacle. Such measures succeed to a limited extent, but nonetheless require the ad hoc intervention of personnel and, moreover, do not succeed to the same extent that a more permanent solution would.
Accordingly, there exists a need for a collapsible, selectively deployable material deflection apparatus adapted for directing into a predetermined receptacle material (e.g., mail pieces) discharged from a discharge chute.
In a typical embodiment, a deflector plate system includes a base frame adapted for one of permanent and removable dependence from the main framework supporting a material-guiding discharge chute. Reciprocably depending from the base frame is a deflector-plate support structure adapted for rearward and forward reciprocating motion with respect to the base frame along a reciprocation axis between a rearwardmost retracted position and a forwardmost extended position. Variations of a deflector-plate support structure include laterally spaced right and left, elongated frame members extending along, but not necessarily parallel to, the reciprocation axis or to one another. Pivotably attached to the right and left frame members are, respectively, right side and left side deflector plates. Each side deflector plate pivots about a side-plate pivot axis extending along, but not necessarily parallel to, the respective one of the right and left frame members from which that side deflector plate depends and along, but not necessarily parallel to, the reciprocation axis. Moreover, each side deflector plate includes an inner face, and outer face, a base edge, a distal edge opposite the base edge, and rear and front edges, the base edge being the edge, as between the base and distal edges, that is closer to the side-plate pivot axis.
In various embodiments, a front deflector plate pivotally depends from each of the right and left side plates. Each of the right and left front plates is pivotable about a front-plate pivot axis extending along the front edge of the side plate from which that front plate depends. Each front plate includes an inside face, an outside face, a base edge, a distal edge opposite the base edge, and upper and lower edges, the base edge being the edge, as between the base and distal edges, that is closer to the front-plate pivot axis.
In still additional embodiments, a rear or tail deflector plate pivotably depends from each of the right and left side plates. Each of the right and left tail plates is pivotable about a tail-plate pivot axis extending along the rear edge of the side plate from which that tail plate depends. Each tail plate includes an interior face, an exterior face, a base edge that extends along the tail-plate pivot axis, a top edge, and bottom edge and, depending on whether the tail plate includes more than three edges, a distal edge opposite the base edge. In an embodiment in which a tail plate includes only three edges, the tail plate is triangular with the top and bottom edges meeting at angle opposite the base edge of the tail plate. The reason for the inclusion of triangular tail plates in various embodiments will be more fully explained in the detailed description below.
In an illustrative environment, the base frame of the deflector plate system is either removably or permanently attached to a framework such that the base frame is disposed underneath the forwardly declining surface of a material-guiding chute. Typically, such a chute further includes material-guiding side walls depending upwardly from the forwardly declining surface and a material discharge (or drop-off) edge defining the terminus of the forwardly declining surface. The deflector plate system is selectively positionable into alternative storage and operative attitudes or states.
An illustrative storage attitude is one in which the deflector plates are collapsed and the deflector-plate support structure has been urged rearwardly toward its rearwardmost position with respect to the base frame. In the illustrative environment in which the base frame is disposed underneath the forwardly declining surface of a material-guiding chute, the deflector plates are sufficiently collapsible so as to assume a profile low enough to clear the material discharge edge of the chute as the deflector-plate support structure is urged toward its rearwardmost position. A storage attitude is, furthermore, typically one in which the deflector-plate support structure is sufficiently retracted that at least a majority portion of the length of each collapsed right and left side plate is disposed rearwardly of the chute discharge edge. In various embodiments, the side and front plates are planar and collapsible to such an extent that one of (i) at least a portion of the inside face of a front plate is overlayingly juxtaposed (e.g., overlapped, but not necessarily in contacting engagement) with a portion of the inner face of the side plate with which it is pivotably attached and (ii) at least a portion of the outside face of a front plate is overlayingly juxtaposed with a portion of the outer face of the side plate with which it is pivotably attached. In at least some versions further including tail plates, the tail plates are planar and collapsible to such an extent that one of (i) at least a portion of the interior face of a tail plate is overlayingly juxtaposed with a portion of the inner face of the side plate with which it is pivotably attached and (ii) at least a portion of the exterior face of a tail plate is overlayingly juxtaposed with a portion of the outer face of the side plate with which it is pivotably attached. xe2x80x9cOverlaying juxtapositionxe2x80x9d includes not only an overlying relationship with or without actual contacting engagement, but also a relationship in which two plates at least partially overlie and are separated by one or more intermediate plates. For instance, one or more embodiments is possible in which a side plate, front plate and tail plate are all of substantially the same length. If the front plate is folded over the side plate and then the tail plate is folded over the front plate, the faces of the side plate and tail plate closest to the front plate between them are still xe2x80x9coverlayingly juxtaposedxe2x80x9d with one another. Additionally, it would not be inconsistent with the intended meaning of xe2x80x9coverlayingly juxtaposedxe2x80x9d to characterize the inside of the front cover of a closed 300-page book as being overlayingly juxtaposed with the inside of the back cover of the book. A collapsed position is, furthermore, typically characterized in that the right and left side plates are pivoted inwardly toward one another such that their distal edges are brought into relatively close proximity to one another, although, it is to be understood, that embodiments in which the side plates are collapsed by pivoting them outwardly away from one another are within the scope and contemplation of the invention.
In order to bring a typically embodied and situated deflector plate system from a storage attitude to an operative attitude, a user first draws the deflector-plate support structure forwardly toward himself or herself until at least the rear edges of the right and left side plates are forward of the chute discharge edge. The user then pivots the side plates from their relatively horizontal positions to more upright positions in which the distal edges of the side plates are higher than the discharge edge of the chute. Once the side plates are sufficiently upright, the front plates can be pivoted such that they extend toward one another. In a typical embodiment, the front plates depending from the right and left side plates are selectively coupleable and, when coupled, combine to form a xe2x80x9cbackstopxe2x80x9d to prevent the overshooting of material exiting the chute. In alternative embodiments, a single front plate pivotably depending from one of the right and left side plates is selectively coupleable to the other of the first and second side plates to serve as the backstop. The upright side plates serve to deflect mail pieces that exit the discharge chute at sidewise angles sufficiently large that such mail pieces would otherwise miss the receptacle below the chute.
In embodiments including tail plates, the tail plates are pivoted from a folded position toward the chute. In various versions, each tail plate includes an edge that inclines as it extends rearwardly of the tail plate base edge. The rearward inclination of the edge facilitates the extension of the tail plate rearward of the chute discharge edge and along the sloped chute surface. If the material-guiding side walls of the chute are spaced at a greater distance than the side plates of the deflector plate system, the tail plates of a typical version can be angled so as to diverge rearwardly with respect to one another into the chute to channel material that slides down the sloped surface of the chute near one of the material-guiding side walls into the area defined inside the side and front plates of the deflector plate system.
In various implementations, when the deflector plates are in a deployed state, the base edges of the side plates and the lower edge of the at least one front plate combine with the discharge edge of the chute, as viewed from above, to define an open xe2x80x9cmaterial acceptance regionxe2x80x9d through which material can descend to a predetermined location below the acceptance region. A receptacle situated below the acceptance region should have a perimeter extending to the outside of the acceptance region in all directions to ensure that material that descends through the acceptance region settles in the receptacle. As shown in illustrative embodiments in the drawings, the deflector plates in various embodiments are sloped when deployed so as to facilitate xe2x80x9cfunnelingxe2x80x9d of material into the acceptance region.
In still further embodiments, the base frame is mounted for pivotable motion about a vertically extending axis such that the deflector-plate support structure can be pivoted clockwise and counterclockwise along a horizontal plane.
Representative embodiments of the invention are more completely described and depicted in the following detailed description and the accompanying drawings.